It is our objective to identify and characterize the components of the brush border membrane, their interactions, and their contributions to digestive-absorptive function. These studies are directed especially toward the membrane-associated oligosaccharidases and oligopeptidases of the membrane transport systems which subserve absorption of the products of hydrolase action, and the relationship between hydrolysis and transport. BIBLIOGRAPHIC REFERENCES: Crane, R. K. Digestion and Absorption: Water-soluble Organics. International Review of Physiology, Gastrointestinal Physiology II. Vol. 12, ed. R. K. Crane., University Park Press, Baltimore, 1977 pp. 325-365. Crane, R. K. The Gradient Hypothesis and Other Models of Carrier-Mediated Active Transport. Rev. Physiol. Biochem. Pharmacol. Vol. 78, Springer-Verlag, 1977, pp. 99-159.